Navigation systems are generally configured to receive an input of a desired destination from a user, to locate that destination on map information either stored in local memory or accessible from remote memory using a wireless connection and to algorithmically determine a route to the destination using roadway information locally stored or otherwise accessible. The route is then output as an overlay of a line of multiple segments, if necessary, that can be overlaid on an image of the map itself, as well as a set of turn-by-turn route guidance instructions. Accordingly, a driver of a vehicle including navigation functionality, either as a stand-alone system or integrated into a vehicle infotainment system, can control vehicle to maintain it along the indicated path, can follow the turn-by-turn instructions, or some combination of the two to result in the vehicle reaching the desired destination.
The turn-by-turn instructions are typically communicated typographically or by voice commands output by the vehicle's speaker system. Often, listening for verbal instructions from navigation system is the least distracting of previously-available means of receiving route guidance instructions, as it does not require the driver to direct his or her view from the road. However, road noise, speaker volume level, or conversation can make it difficult for the driver to consistently accurately receive the verbal instructions, often requiring confirmation or receipt using the typographical output. Accordingly, further non-verbal and non-typographical communication systems may be helpful to drivers in using a vehicle navigation system.